Galvanic battery



Patented July 4, 1939 UNITED STATES PATENT OFFICE czmvmc BATTERY ErichMarhenkel, Berlin, Germany, assignor to Tcrtrix Chemische FabrikAktiengesellschaft, Berlin, Germany, a joint-stock company of Germany NoDrawing. Application August 10, 1936, Serial No. 95,286. In GermanyAugust 15, 1935 6 Claims. (Cl. 136-103) My invention relates toimprovements in galcorresponding to the intensity of the discharge vanicbatteries, and more particularly in batteries current and the durationof the discharge. Prac-- of the type in which the electrolyte containssuch tically this is the case if the said amount is about ions as areliable to be transformed into hydrox- 50 grammes per 100 cubiccentimeters of the ides and to be deposited in this form on theposifinished oxygen transmitting positive electrode tive electrode thustending to clog the pores of (without its terminal). The said positiveelecthe said positive electrode, and in which the positrode ismanufactured by thoroughly mixing fine tive electrode is depolarized bythe oxygen of air crystalline sal ammoniac with the active carbon,contained therein. The said electrolyte contains adding thereto a slightamount of the electrolyte,

) for example sal ammoniac and zinc chloride. As shaping from themixture the electrode, and com- 10 is known in the art, such ions areeither zinc or bining the components by high pressure. manganese ions,which are developed either from The amount of other derivatives ofammonia a negative zinc electrode in an electrolyte of any to be addedto the electrode is substantially the composition, or from anelectrolyte containing same.

5 zinc or manganese and having a negative elec- Ihave discovered that inan electrode with detrode of any composition immersed therein. Inpolarization by air the depolarizing action is not positive electrodesin which depolarization is efimpaired in any way even if the content ofsal fected by chemical depolarizers such as manammoniac is high, thereason-being that in this ganese oxide the amount of solid sal ammoniaccase the depolarizer is the air contained within in the electrode mustbe small, in order to prethe electrode. A particularly important resultvent reduction of the depolarization intensity or is obtained by thehigh addition of sal ammoniac high destruction of the zinc. I havediscovered, in so far as the precipitation of the salts of zinc that inpositive electrodes in which depolarization or manganese on or withinthe electrode is reiS efie y the O y Of the amount Sal duced. In thisrespect use has been made of s ammoniac may comparatively hi a d thatthe fact that the precipitation of the said salts 26 a high amount ofsal ammoniac in the said eleof ammonia, and more particularly of thehytrode with air depolarization produces valuable droxide of the zinc orthe manganese, is safely results which will be described hereinafter.avoided where sal ammoniac is present in excess,

Further, I have found that similar results are the sal ammoniaccontained within the electrode attained when in lieu of sal ammoniao orin adbeing dissolved, in accordance with the intensity 30 dition t0 salammon ac O a c derivatives 0f of the current discharge and the durationof the ammoniac such for example as monomethylamindischarge, by thewater produced on or within the chlorohydrate are present in the saidelectrode, electrode, and the dissolved sal ammoniac safely suitableorganic derivatives being such which preventing precipitation of theaforesaid salts.

3 contain NH r NH; groups, Thus any inactivation and more particularlyany The positive electrode may consist, for exincrustation of theelectrode on the surface thereample, of a porous body of active carbonhaving Within the Same are P ed. an excess of air. To the said electrodeI add a I claim: comparatively high proportion of sal ammoniac 1. Theherein described galvanic battery, comor an organic derivative ofammoniac such as prising a positive electrode of the type in which 40monomethylaminchlorohydrate, or both sal amdepolarization is effected bythe oxygen of air moniac and an organic derivative of ammonia, containedwithin the electrode, a negative electhe amount of the said substance orsubstances trode, and an electrolyte containing such metal being suchthat, with the intensity of the disions as are liable to be transformedinto hy-' i charge current and the duration of the discharge droxidesand to be deposited on the positive elecoccurring in service and causedby the regular trode, in which the said positive electrodeconconcentration of the zinc or manganese ions, tains solid sal ammoniacin an amount such that, deposition of zinc ormanganese salts,particularwith the metal-ion concentration corresponding ly in the formof the hydroxides, on or within to the intensity of the dischargecurrent and the b the electrode is prevented. Ihave found that thisduration of the discharge occurring in service, 60

result is attained if the amount of sal ammoniac precipitation of metalsalt on and within the posior an organic derivative of ammonia in theelective electrode is prevented. trode is such that there is always anexcess of sal 2. The herein described galvanic battery, comammoniac oran organic derivative of ammonia prising a positive electrode of thetype in which i over the zinc or manganese-ion concentrationsdepolarization is effected by the oxygen of ai contained within theelectrode, a negative electrode, and an electrolyte containing a zincsalt, in which the said positive electrode contains solid sal ammoniacin an amount such that, with the zinc-ion concentration corresponding tothe intensity of the discharge current and the duration of the dischargeoccurring in service, precipitation of zinc salt on and within thepositive electrode is prevented.

3. Thejgherein described galvanic battery, comprising a positiveelectrode of the type in which depolarization is effected by the oxygenof air contained within the electrode, a negative electrode, and anelectrolyte containing a manganese salt, in which the said positiveelectrode contains solid sal ammoniac in an amount such that, with themanganese-ion concentration corresponding to the intensity of thedischarge current and the duration of the discharge occurring inservice, precipitation of manganese salt on and within the positiveelectrode is prevented.

4. Galvanic battery as claimed in claim 1, in which the amount of salammoniac within the positive electrode is about 50 grammes per- 100cubic centimeters of the volume of thefinished oxygen-transmittingpositive electrode.

5. The herein described galvanic battery, comprising a. positiveelectrode of the type in which depolarization is effected by the oxygenof air contained within the electrode, a negative electrode, and anelectrolyte containing such metal ions as are liable to be transformedinto hydroxides and to be deposited on the positive electrode, in whichthe said positive electrode contains solid monomethylaminchlorohydratein an amount such that, with the metal-ion concentration correspondingto the intensity of the discharge current and the duration of thedischarge occurring in service, precipitation of metal salt on andwithin the positive electrode is prevented.

6. The herein described galvanic battery, comprising a positiveelectrode of the type in which depolarization is effected by the oxygenof air contained within the electrode, a negative electrode,-and anelectrolyte containing such metal ions as are liable to be transformedinto hydroxides and to be deposited on the positive electrode, in whichthe said positive electrode contains 'a solid salt of the groupconsisting of salammoniac and monomethylamin-chlorohydrate in an amountsuch that, with the metal-ionconcentration corresponding to theintensity of the discharge current and the duration of-the dischargeoccurring in service, precipitation of metal salt on and within thepositive electrode is prevented.

ERICH MARHENKEL.

